Electric heater.



A. O. DUNHAM.

ELECTRIC HEATER.

APPLICATION FILED APR.16, 1907.

905, 1 59. Patented Dec. 1, 1908.

Inventor: Austin C. Dun ham,

PATENT OFFICE.

AUSTIN C. DUNHAM, OF HARTFORD, CONNECTICUT.

ELECTRIC HEATER.

Specification of Letters Patent.

Patented Dec. 1, 1908.

Application filed April 16, 1907. Serial No. 368,460.

T 0 all whom "it may concern:

Be it known that I, At'srnv C. DUNHAM, a citizen of the United States,residing at Hartford, in the county of Hartford and State ofConnecticut, have invented certain new and useful Improvements inElectric Heaters, of which the following is a specification.

This invention relates to electric heaters and has for its'object theprovision of a device of this character in which the energy of theelectric current will be converted into heat and distributed in a safeand efficient manner.

My invention relates more specifically to electric heaters. of the typeused for Warming theair of rooms. This type of heater requires a largeradiating surface in proportion to the amount of heating surface, and itis one of the objects of my invention to supply a heater in which theradiating surface will distribute the heat uniformly and efficiently. Inthis form of heater a fluid, such as air, water, oil or the'like, iscaused to circulate within a closed casing thereby carry ing the heatfrom the point at which it is generated throughout an extensiveradiating surface.

My invention therefore consists in the features of construction and inthe arrangement and combination of elements hereinafter set forth andparticularly pointed out in the claims annexed to and forming a part ofthis specification.

In the accompanying drawings, Figure 1 is an elevation partly in sectionof one form of my invention; Fig. 2 is a sectional view taken on theline 22 of Fig.3 looking in the direction of the arrow; and Fig. 3 is asectional view taken on the line 3-3 of Fig. 1.

Referring to the drawings, 10 is a metallic casing made of sheet iron orany good heat conducting material. This casing is corrugated as shown inthe drawings so as to approximate the form of a standard radiator. Theparticular form, however, of the casing is not of the essence of myinvention, the main object being to secure a large radiating surface.This casing is mounted upon a base 11 and provided'with a cap or cover12, both of which may be of cast-iron. The corrugated casing is securedbetween the top and bottom castings inany desired way, as for instanceby soldering, so as to give a waten tight joint. Extending from end toend at l the bottom of the casing between the corrugated sides is ametallic tube, 13, the ends of which are flanged over the ends of thecasing at 14 so as to make a tight joint. This tube is adapted toreceive a heating unit 15, the particular form of which constitutes nopart of my invention. I have found, however, that the unit disclosed inthe patent to George E. Stevens, No. 803,795 serves the purpose verywell, and for purposesof illustration I have shown my heater inconnection with this unit: Other types of heating ing from the spirit ofmy invention. Arranged within the casing and adjacent to the inner endsof the corrugations are parallel plates 16 which extend throughout thelength of the casing transversely of the corrugations. The plates,however, stop within a short distance of the top and bottom of thecasing so as to cause the chamber formed by the plates 16 to communicateat the top and bottom with the lateral chambers formed by thecorrugations. At the bottom the plates 16 are curved around the tube,13,as shown. In order to permit of this curvature of the plate, the latteris cut away so as to form strips or'tongues 17 which fit in between thecorrugations, as shown. At the top of the casing I provide an air valveor pet cock 18 and at 19 is a plug which may be removed for filling thecasing.

The mode of operation of my device is as follows: The casing is filledwith water, oil or the like to a point just below the cock 1-8 and anelectric current is turned on to the unit 15 which will quickly rise intemperature. This will cause the water in the immediate vicinity of theunit and between the plates 16 to rise, the plates keeping the warmwater and the cooler water separated. The water will thus rise andpassing over the top of the plates on both sides will descend downwardthrough the corrugations so as to replace the warm water which has goneupward in the central chamber. This will cause a circulation of water inthe direction of the arrows, c. the water will pass upward through thecentral chamber and downward through the two sides, thus drawing theheat away from the heating unit and distributing it throughout a largeradiating surface thereby causing a unform temperature throughout thecasing. I consider the arrangement of the plates 16 which operate asdeflectors or battle-plates units may be used, however, without departanimportant part of my invention since they cause a perfect circulationthroughout the casing by a very simple construction. By arranging theheating unit horizontally Within the bottom of the central chamber thecirculation is also greatly improved.

Many modifications of my invention will suggest themselves tothoseskilled in the art all of which are within the spirit of myinvention-in so far as they fall within the scopeof the annexed claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is,

.1. An electric heater comprising a fluid receptacle having a centralchamber, ,a heating device within said chamber, and lateral chamberscommunicating with the central chamber at the upper and lower portionsthereof.

2. An electric heater comprising a fluid receptacle having a centralchamber, lateral chambers communicating therewith at the top and bottom,and an electric heating unit located horizontally within the bottomportion of said central chamber. 3. An electric heater comprising acorrugated fluid receptacle having a central casmg dividing thereceptacle into communieating chambers, and a heating device lo= catedwithin the bottom portion of said central casing.

4. An electric heater comprising a fluid receptacle having corrugatedsides, a central casing therein dividing the receptacle into chamberscommunicating at the top and bottom thereof, and an electric heatingunit located in the lower portion of said central casing and parallelwith the sides.

5. n electric heater comprising a fluid receptacle having corrugatedsides and parallel plates arranged within the casing adjacent to thecorrugations so as to form a central chamber communicating with thelateral corrugated chambers at the top and bottom, and an electricheating unit arranged within the lower portion of the central chambertransversely of the corrugations.

6. In a heater, the combination with a vertical chamber, of a lateralvertical chamber communicating at its top and bottom with said Verticalchamber, and a heating unit located within the walls of said verticalchamber.

7. In a heater, the combination with two or more vertical chamberscommunicating at their top and bottom to'allow a gravity hot watercirculation through said chambers, and a heating unit located in thepath {if said water circulation through said chamers.

8. A heater, comprising two or more vertical chambers, a heating unitwithin one of said chambers, said chambers having communicating openingsat the upper and lower ends thereof, with the top of the lowercommunicating opening below the top of the heating unit. a

9. A heater, comprising a single vertical chamber, a verticallycorrugated sidewith the inward bends of .the corrugations in contactwith the side wall of said vertical chamber, thereby forming verticalchambers transverse to said single chamber, a heating unit in saidsingle chamber, and with said wall of said single chamber provided withopenings above and below said heating unit communicating with each ofsaid transverse chambers. 2

10. A heater, comprising two or more vertical chambers, with a dividingwall between said chambers, said wall provided with openings betweensaid chambers at the top and bottom of said chambers, a heating unitlocated at one side of the plane of said dividing wall, with saiddividing wallextending tothe top of said heating unit.

11. A heater, comprising two or more chambers, with a vertical dividingwall between said chambers, said wallprovided with openings between saidchambers at the top and bottom of said chambers, a heating unit locatednear the bottom of one of said chambers, with said vertical dividingwall opposite said heating unit bent outward and around said heatingunit.

In witness whereof, I have hereunto set my hand this twelfth day ofApril, 1907.

AUSTIN G. DUNHAM.

Witnesses ERNEST S. Norrmc, F. A. IsLnmI

